1. Field of the Invention
The present invention generally relates to manufacturing technology of a structural body formed by including a glass substrate, and in particular relates to manufacturing technology preferable in manufacturing a fluidic device such as a droplet discharging head.
2. Description of the Related Art
In recent years, development of devices employing MEMS (micro electro mechanical systems) technology is being conducted actively, and, for instance, this is being applied to the manufacture of various fluidic devices such as droplet discharging heads, biochips, micropumps and so on. Various researches have been conducted regarding the structure of the foregoing devices, and, for example, a structure employing a bonding body formed from a silicon substrate and a glass substrate is being used. With this kind of fluidic device, grooves, holes (recesses), through-holes and the like are formed in the silicon substrate and glass substrate in order to create a fluid channel for passing some type of solution within the device or creating an actuator (moving element) or other functional units for realizing prescribed operations.
The process of forming a fluid channel or other functional units in the glass substrate or the like is relatively carried out by processing the surface side of the glass substrate or the like, and this processing is often a combination of the photolithography technique and etching technique. Meanwhile, the process of forming the likes of a through-hole in the glass substrate or the like is carried out by performing processing in the plate thickness direction of the glass substrate or the like, and this processing is often a mechanical processing employing a cutting tool such as a drill. Further, in recent years, as one technique of performing microfabrication to a glass substrate, known is a processing technique of creating a difference in the etching speed between the irradiated region and non-irradiated region by irradiating light to a desired position of the glass substrate, and removing the irradiated region with etching processing. This kind of technique is described in, for instance, the gazette of Japanese Patent Laid-Open Publication No. H9-309744.